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United States Patent | 5,102,432 |
Prasad | April 7, 1992 |
Very high purity nitrogen is produced by air separation in a three stage membrane system in which the third stage permeate is recycled to the second stage and the membrane surface area is distributed between the stages to achieve high product recovery and process performance. Other gas separations, such as argon from oxygen, can likewise be achieved by thus using a three stage membrane system.
Inventors: | Prasad; Ravi (East Amherst, NY) |
Assignee: | Union Carbide Industrial Gases Technology Corporation (Danbury, CT) |
Appl. No.: | 624969 |
Filed: | December 10, 1990 |
Current U.S. Class: | 95/54; 96/9 |
Intern'l Class: | B01D 053/22 |
Field of Search: | 55/16,66,68,158 |
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